Go for launch

Today, SpaceX launched its Demo-2 mission, the first manned mission leaving from US soil since 2011, and our first capsule launch since 1975. If all goes well, the Dragon will dock with the ISS tomorrow morning, then spend the summer there before a splashdown in September. In this post, I’d like to talk about my feelings and opinions about this historic moment and what I think it means for all of us.

As you may have guessed from reading my posts here and elsewhere, as well as my books, I am a space nut. I don’t deny it. Space has captivated me since I was a child, when I would read books about the Apollo missions, encyclopedia articles about the solar system and the planets. Cartoons involving space, most of them made in the early ’60s (before we had ventured beyond Earth orbit), captivated me. TV and movies mostly meant Star Trek, Star Wars, and eventually the Stargate franchise, as well as the far more realistic Apollo 13—still one of my favorite movies—and even Space Camp.

Since those days, I’ve expanded my repertoire. I’ve read Andrew Chaikin’s A Man on the Moon, the go-to account of the Apollo program and its precursors, at least a dozen times. I eagerly watched its TV version, From the Earth to the Moon, a few years before that, and my eyes were glued to the screen for 2007’s When We Left Earth. Add in the other historical accounts, the futurists’ ideas, the rocketry textbooks, and even games like Kerbal Space Program, and you get the picture. Space will always grab my attention.

But the real-life space program is often depressing. NASA is, in certain circles, a running joke. “Boldly going nowhere since 1972” is a faux slogan I’ve seen and spread in reference to what was, in my teenage years, the only government program I truly supported. The Russians aren’t really any better; they at least have the excuse of communism and its aftermath. The Chinese are too secretive and suspicious, and no one else is even bothering with manned spaceflight.

I thought the X-Prize would change that. I watched the Scaled Composites flights with stars in my eyes, believing this would finally be the dawn of a new Space Age. Because the first one was, in my opinion, one of the three most pivotal periods in modern human history—the others being the Enlightenment and Industrial Revolution, in case you were wondering. The heady days of 1957-72 directly begat the Information Age of 1992-2016, as well as our present time, which I feel is better labeled a Misinformation Age. A new space race, even one driven mostly by capitalistic concerns of profit and shareholder value, will bring a new technological revolution. There’s no doubt in my mind. And the benefits will be felt far beyond the space-loving community. Apollo made computers popular. What will the first mission to Mars give us?

In 2004, it looked like that was coming true in real time. SpaceShipOne was reaching the Karman Line, the boundary between our world and the vast void beyond, and pocketing a few million dollars in the process. Richard Branson was hyping trips around the moon. Robert Bigelow had inflatable space stations and lunar colony modules on the drawing board. Elon Musk, Peter Diamandis, Jeff Bezos, John Carmack…entrepreneurs were getting in the game, and so were tech giants. Google announced a prize for an unmanned lunar lander (nobody won it, alas), and one of the team leaders even shared my name. The dream was alive.

And then it wasn’t.

The Great Recession was a setback for space as much as any other sector. Launch dates began to slip faster than the stock market. SpaceX had a few bad accidents, plus a lot of red tape. Even the government stuff was going badly: important science missions like SIM and TPF were scrapped, Kepler barely got off the ground, and we still don’t have that Europa lander. The Obama administration didn’t help matters, as they prioritized earth science and political causes such as global warming and diversity over the core mission of NASA.

In 2008, I looked back on the Bush presidency with an opinion that has remained unchanged over the past twelve years: the Vision for Space Exploration was the only truly good thing he did. That was killed early in Obama’s first term—he campaigned on it!—and replaced with…nothing. Seriously. Rather than reach for the stars, our previous president was content to go in circles. There’s a metaphor there. I think it’s pretty obvious.

The final Shuttle launch was a sad time for me, a dark time. Sure, I’ve had much darker moments since, but that day felt like…well, like I was watching a friend die, and I could do nothing to stop it. It was a day that a childhood dream was finally, fatally crushed. Astronauts were going nowhere, and now they couldn’t even do that without hitching a ride from our former enemies!

In the years since, I had to get my space fix wherever I could find it. I went back to reading science fiction, which I had avoided for years because of the sheer despair it caused when I thought about how far away we are from doing anything like what I was reading. Eventually, reading became writing, a process that culminates with the imminent release of Innocence Reborn, my first novel set in space.

But I keep following SpaceX. They’re the only ones left from those wonderful early days of the commercial space race, and they’re actually doing something. Elon Musk has grand plans, along with both the will and the means to pull them off. Whether his team can, I don’t know, but I’m hoping.

We need space. Space is our future, in both the literal and the metaphorical senses. Moon missions, Mars missions, asteroid mining, and space hotels all offer something to humanity as a whole. We gain scientific knowledge from exploring new places, material resources from the untapped riches awaiting us, and an important intangible: something to strive for.

Every night, we can look up and see infinity. Pinpricks of light impossibly far away, for the most part. But some of the things in the sky are much closer. They’re within our grasp, but only if we want to reach. Today should long be remembered as the day America finally started to stretch out its hand again.

Exoplanets for builders

In just over two decades, we’ve gone from knowing about nine planets (shut up, Pluto haters) to recognizing the existence of thousands of them. Almost all of those are completely unsuitable for life as we know it, but researchers say it’s only a matter of time before we find “Earth 2.0”. Like any other 2.0 version, I’m sure that one will have fewer features and be harder to use, but never mind that.

As so many science fiction writers like to add in a large helping of verisimilitude, I thought I’d write a post summarizing what we know about planets outside our solar system, or exoplanets, as we enter 2017. Keep in mind that there’s a lot even I don’t know, although I’ve been following the field as a lay observer since 2000. Nonetheless, I hope there’s enough in here to stimulate your imagination. Also, this will necessarily be a technical post, so fantasy authors beware.

What we know

We know planets exist beyond our solar system. They’ve been detected by the way they pull on their stars as they orbit (the Doppler or radial velocity method), and that’s how we found most of the early ones. The majority of those known today, thanks to the Kepler mission, have been discovered by searching for the change in their stars’ light intensity as the planets pass before them: the transit method. In addition, we have a few examples of microlensing, where the gravity of a planet bends the light of a “background” star ever so slightly. And we’ve got a handful of cases where we’ve directly imaged the planets themselves, though these tend to be very, very large planets, many times the size of Jupiter.

However we see them, we’re sure they’re out there. They can’t all be false positives. And thanks to Kepler, we’ve got enough data to start drawing some conclusions. Of course, these must be considered subject to change, but that’s the way of science.

First, our solar system, with its G-type star orbited by anywhere from eight to twenty planets (depending on who’s counting) starting at about 0.3 AU, looks very much like an outlier. We don’t have a “hot Jupiter”, a gas giant exceedingly close to the star, with an orbit on the order of days. Nor do we have a “warm Neptune” (a mid-range gaseous planet somewhere in the inner system) or a “super-Earth” (a larger terrestrial world, possibly with a thick atmosphere). This doesn’t mean we’re unique, though, only that we can’t assume our situation is the norm.

Second, we’ve got a pretty good idea about which stars have planets. To a first approximation, that’s all of them, but the reality is a little more nuanced. Bright giants don’t have time to form planets. Small red dwarfs don’t have the material to create Jupiter-size giants. Neither of these statements is an absolute—we’ve got examples of gas giants around M-class stars—but they’re tendencies. Everything else, seemingly, is up in the air.

What we can guess

Planets do appear to be everywhere we look. There are more of them around M stars, but that’s largely because there are so many more M stars to begin with. A lot of stars have planets with much closer orbits, so close that you wouldn’t expect them to form. Gas giants aren’t restricted to the outer system, like they are here. And there’s a whole class, the super-Earths, that we never knew existed.

We can make some educated guesses about some of these planets. For example, many of the super-Earths, according to computer simulations, may actually be tiny versions of Neptune, so-called “gas dwarfs”. If that’s true, it severely cuts our number of potentially habitable worlds. On the other hand, the definition of the habitable zone has only expanded since we started finding exoplanets. (Even in our own solar system, what once was merely Earth and maybe the Martian underground now includes Europe, Titan, Enceladus, Ganymede, Ceres, the cloud tops of Venus, and about a dozen more exotic locales.) Likewise, studies suggest that a tide-locked planet around a red dwarf star doesn’t have to be frozen on one side and scorched on the other.

We’ve got a few points where we don’t even have data, though. One of these, possibly the most important for a writer, is the frequency of Earthlike worlds. By “Earthlike”, I don’t simply mean terrestrial, but terrestrial and capable of having liquid water on the surface. Where’s the closest one of those? Until about a year ago, the answer might have been anywhere from 15 to 500 light-years away. But then came Proxima b. If it turns out to be potentially habitable—in the month and a half between my writing this post and it going up, we may very well know—then that almost ensures that Earthlike worlds are everywhere. Because what are the chances that the next-closest star to the Sun has one, too?

Creating a planet

For the speculative writer, this lack of knowledge is a boon. We have the freedom to create, and there are few definite boundaries. Want to put a gas giant in the center of a star’s habitable zone, with multiple Earthlike moons? We can’t prove it’s impossible, and the real-life counterpart might really be out there, waiting to be found.

Basically, here’s a rundown of some of the factors that go into creating an exoplanet:

  • Star size: Bigger stars are shorter-lived, but smaller ones require their “classically” habitable planets to be much closer, to the point where they’ll likely be tide-locked. G-type dwarfs like ours are a happy medium, but not a common one: something like 1% of stars are in the G class, and there’s not much data saying that planets are more likely around them.

  • Star number: Most stars, it seems, are in multiple systems. Binaries can host planets, though; we’ve detected a class of “Tatooine” planets (named after the one in Star Wars, because scientists are nerds) circling binary systems. For close binaries, this is a fairly stable arrangement, but with huge complexities in working out parameters like temperature. Distant binaries like Alpha Centauri can instead have individual planetary systems.

  • Planet size: We used to think there was a sharp cutoff between terrestrial and gaseous planets, based on the difference between the largest terrestrial we knew (Earth) and the smallest gas planets (Uranus and Neptune). Now we know that’s simply not true. It’s more of a continuum, and there may be super-Earths much larger than the smallest mini-Neptunes. And those gas dwarfs appear to be the most common type of planet, but that could be nothing more than observation bias, the way we thought hot Jupiters were incredibly common ten years ago. On the smaller end of the scale, we haven’t found much, but there’s no reason to expect that exoplanet analogues of Mars, Mercury, Pluto, and Ganymede don’t exist.

  • Surface temperature: This is a big one, as it’s critical for life as we know it. We know that liquid water exists between 0° and 100°C (32–212°F), with the upper bound being a bit fluid due to atmospheric pressure. That 100 (or 180) degrees is a lot of room to play with, but remember that it’s not all available. DNA, for example, can break down above about 50°C. Below freezing, of course, you get into subsurface oceans, which might be fun for exploration purposes.

  • Atmosphere: Except for a couple of gas giants, we’ve got nothing here. We have no idea if the nitrogen-oxygen mix of Earth is common, or if most planets we find would be CO2 pressure cookers like Venus. Or they could retain their primordial hydrogen-helium atmospheres, or be nearly airless like Mars. Something tells me that we’ll find all of those soon enough.

  • Life: And so we come to this. Life, we know, changes a planet, just as the planet changes it. A biosphere will be detectable, even from the distance of light-years. It will get noticed, once telescopes and instruments are sensitive enough to see it. And it will stand out. Some chemicals just don’t show up without life, or at least not in the quantities that it brings. Methane, O2, and a few others are considered likely biotic markers. The million-dollar question is just how likely life really is. Is it everywhere? Are there aliens on Proxima b right now? If so, are they single-celled, or possibly advanced enough to be looking back at us? Here is the writers’ playground.

What’s to come

Assuming the status quo—never a safe assumption—our capability for detecting and classifying exoplanets is only expected to increase in the coming years. But I’ve heard that one before. Once upon a time, the timeline looked like this: Kepler in 2004 or 2005, the Space Interferometry Mission (SIM) in 2009, and the Terrestrial Planet Finder (TPF) in 2012. In reality, we got Kepler in 2009 (it’s now busted and on a secondary mission). TPF was “indefinitely deferred”, and SIM was left to languish before being mercy-killed some years ago. The Europeans did no better; their Darwin mission suffered the same let’s-not-call-it-cancelled fate as TPF. Now, both missions might get launched in the 2030s…but they probably won’t.

On the bright side, we’ve got a small crop of upcoming developments. TESS (Transiting Exoplanet Sky Survey, I think) is slated to launch this year—I’ll believe it when I see it. The James Webb Space Telescope, the Hubble’s less-capable brother, might go up in 2018, but its schedule is going to be too crowded to allow it to do more than confirm detections made by other means.

Ground-based telescopes are about at their limit, but that hasn’t stopped us from trying. The E-ELT is expected to start operations in 2024, the Giant Magellan Telescope in 2025, and these are exoplanet-capable. The Thirty Meter Telescope was supposed to join them in about the same timeframe, but politically motivated protests stopped that plan, and the world is poorer for it.

Instead of focusing on the doom and gloom, though, let’s look on the bright side. Even with all the problems exoplanet research has faced, it’s made wonderful progress. When I was born, we didn’t know for sure if there were any planets outside our own solar system. Now, we’re finding them everywhere we look. They may not be the ones science fiction has trained us to imagine, but truth is always stranger than fiction. Forget about “Earth 2”. In a few years, we might have more Earths than we know what to do with. And wouldn’t that make a good story?

On space battles

It’s a glorious thing, combat in space, or so Hollywood would have us believe. Star Wars shows us an analog of carrier warfare, with large ships (like Star Destroyers) launching out wing after wing of small craft (TIE Fighters and X-Wings) that duke it out amid the starry expanse. That other bastion of popular science fiction, Star Trek, also depicts space warfare in naval terms, as a dark, three-dimensional version of the ship-to-ship combat of yore. Most “smaller” universes ape these big two, so the general idea in modern minds is this: space battles look like WWII, but in space.

Ask anyone who has studied the subject in any depth, however, and they’ll tell you that isn’t how it would be. There’s a great divide between what most people think space combat might be like, and the form the experts have concluded it would take. I’m not here to “debunk”, though. If you’re a creator, and you want aerial dogfighting, then go for it, if that’s what your work needs. Just don’t expect the nitpickers to care for it.

Space is big

The first problem with most depictions of space battles is one of scale. As the saying goes, space is big. No, scratch that. I’ll tell you right now that saying is wrong. Space isn’t big. It’s so huge, so enormous, that there aren’t enough adjectives in the English language to encompass its vastness.

That’s where Hollywood runs into trouble. Warfare today is often conducted via drone strikes, controlled by people sitting at consoles halfway around the world from their targets. We rightfully consider that an impersonal way of fighting, but what’s striking is the 10,000 miles standing between offense and defense. How many Americans could place Aleppo on a map? (The guy that finished third in the last presidential election couldn’t.) Worse, how would you make a drone strike dramatic?

In space, the problem is magnified greatly. Ten thousand miles gets you effectively nowhere. From the surface of Earth, that doesn’t even take you past geostationary satellites! It’s over twenty times that to the Moon, and Mars is (at best) about another 100 times that. In naval warfare, it became a big deal when guns got good enough to strike something over the horizon. Space has no horizon, but the principle is the same. With as much room as you’ve got to move, there’s almost no reason why two craft would ever come close enough to see as more than a speck. A range of 10,000 miles might very well be considered point-blank in space terms, which is bad news for action shots.

Space is empty (except when it isn’t)

Compounding the problem of space’s size is its relative emptiness. There’s simply nothing there. Movies show asteroid belts as these densely packed regions full of rocks bumping into each other and sleek smuggler ships weaving through them. And some stars might even have something like that. (Tabby’s Star, aka KIC 8462852, almost requires a ring of this magnitude, unless you’re ready to invoke Dyson spheres.) But our own Solar System doesn’t.

We’ve got two asteroid belts, but the Kuiper Belt is so diffuse that we’re still finding objects hundreds of miles across out there! And the Main Belt isn’t that much better. You can easily travel a million miles through it without running across anything bigger than a baseball. Collisions between large bodies are comparatively rare; if they were common, we’d know.

Space’s emptiness also means that stealth is quite difficult. There’s nothing to hide behind, and the background is almost totally flat in any spectrum. And, because you’re in a vacuum, any heat emissions are going to be blindingly obvious to anyone looking in the right direction. So are rocket flares, or targeting lasers, radio transmissions…

Space plays its own game

The worst part of all is that space has its own rules, and those don’t match anything we’re familiar with here on Earth. For one thing, it’s a vacuum. I’ve already said that, but that statement points out something else: without air, wings don’t work. Spacecraft don’t bank. They don’t need to. (They also don’t brake. Once they’re traveling at a certain speed, they’ll keep going until something stops them.)

Another one of those pesky Newtonian mechanics that comes into play is the Third Law. Every action has an equal and opposite reaction. That’s how rockets work: they spit stuff out the back to propel themselves ahead. Solar sails use the same principle, but turned around. Right now, we’ve got one example (the EmDrive) of something that may get around this fundamental law, assuming it’s not experimental error, but everything in space now and for the near future requires something to push on, or something to push against it. That puts a severe limit on craft sizes, speeds, and operating environments. Moving, for example, the Enterprise by means of conventional thrusters is a non-starter.

And then there’s the ultimate speed limit: light. Every idea we’ve got to get around the light-speed barrier is theoretical at best, crackpot at worst. Because space is huge, light’s speed limit hampers all aspects of space warfare. It’s a maximum for the transmission of information, too. By the time you detect that laser beam, it’s already hitting you.

Reality check

If you want hyperrealism in your space battles, then, you’ll have to throw out most of the book of received wisdom on the subject. The odds are severely stacked against it being anything at all like WWII aerial and naval combat. Instead, the common comparison among those who have researched the topic is to submarine warfare. Thinking about it, you can probably see the parallels. You’ve got relatively small craft in a relatively big, very hostile medium. Fighting takes place over great distances, at a fairly slow speed. Instead of holding up Star Trek as our example, maybe we should be looking more at Hunt for Red October or Das Boot.

But that’s if reality is what you’re looking for. In books, that’s all well and good, because you don’t have to worry about creating something flashy for the crowd. TV and movies need something more, and they can get it…for a price. That price? Realism.

Depending on the assumptions of your universe, you can tinker a bit with the form of space combat. With reactionless engines, a lot of the problems with ship size and range go away. FTL travel based around “jump points” neatly explains why so many ships would be in such close proximity. Depending on how you justify your “hyperspace” or “subspace”, you could even find a way to handwave banked flight.

Each choice you make will help shape the “style” of combat. If useful reactionless engines require enormous power inputs, for instance, but your civilization has also invented some incredibly efficient rockets on smaller scales, then that might explain a carrier-fighter mode of warfare. Conversely, if everything can use “impulse” engines, then there’s no need for waves of smaller craft. Need super-high acceleration in your fighters, but don’t have a way to counteract its effects? Well, hope you like drones, because that’s what would naturally develop. But if FTL space can only be navigated by a human intelligence (as in Dune), then you’ve got room for people on the carriers.

In the end, it all comes down to the effect you’re trying to create. For something like space combat, this may mean working “backward”. Instead of beginning with the founding principles of your story universe, it might be better to derive those principles from the style of fighting you want to portray. It’s not my usual method of worldbuilding, but it does have one advantage: you’ll always get the desired result, because that’s where you started. For some, that may be all you need.